The subject application is related to subject matter disclosed in the Japanese Patent Application No.Hei11-263697 filed in Sep. 17, 1999 in Japan, to which the subject application claims priority under the Paris Convention and which is incorporated by reference herein.
1. Field of the Invention
The present invention is related to an improved receiver/transmitter apparatus by making use of frequencies of microwaves, millimeter waves or the like.
2. Description of the Related Art
A high frequency circuit apparatus in accordance with a conventional technique will be explained with reference to FIG. 1 which is a cross sectional view thereof. The reference 31 designates a base structure constituting the bottom section of a metallic case for example. On the base structure 31, a high frequency circuit portion 32 and a direct current circuit portion 33 are implemented.
The high frequency circuit portion 32 is composed of a carrier plate 321, high frequency circuit elements 322 such as MMICs, FETs and so forth which serve to process high frequency signals and which are located in the carrier plate 321, and a high frequency substrate 323 which are located in the peripheral location of the high frequency circuit elements 322. A circuit patterns 324 such as strip lines for transferring high frequency signals is formed on the principal surface of the high frequency substrate 323 while a ground electrode 325 is formed on the rear surface of the high frequency substrate 323. The ground electrode 325 of the high frequency substrate 323 is joined to the carrier plate 321. The high frequency circuit elements 322 and the circuit pattern 324 are connected to each other by means of wirings W while the circuit pattern 324 and the ground electrode 325 are electrically connected to each other via through halls 326.
The direct current circuit portion 33 is composed of a direct current substrate 331, direct current elements 332 such as condenser chips, resistors and so forth which are located on the direct current substrate 331, a circuit pattern 333 located on the surface of the direct current substrate 331, and a ground electrode 334 formed on the rear surface of the direct current substrate 331. The ground electrode 334 of the direct current substrate 331 is joined to the base structure 31. The circuit pattern 333 formed on the principal surface of the direct current substrate 331 is electrically connected to the ground electrode 334 formed on the rear surface of the direct current substrate 331 via through halls 335.
In the case of the above explained configuration, the high frequency circuit portion 32 and the direct current circuit portion 33 are formed separate from each other while the circuit pattern 324 of the high frequency circuit portion 32 and the circuit pattern 333 of the direct current circuit portion 33 is electrically connected to each other, for example, by means of the wirings W made of gold strips.
Next, another example of the high frequency circuit apparatus in accordance with a conventional technique will be explained with reference to FIG. 2.
The reference 41 designates a base structure constituting the bottom section of a metallic case for example. A multilayer substrate 42 is located on the base structure 41. The multilayer substrate 42 is composed of first to third substrates 421, 422 and 423 which are layered in this order from the top. High frequency circuit elements 43 such as MMICs, FETs and so forth are located in the center position together with direct current elements 44 such as condenser chips, resistors and so forth which are located on both sides of the high frequency circuit elements 43 and a circuit pattern 45 for transferring high frequency signals and direct current signals.
For example, circuit patterns 46 and 47 for transferring direct current signals are provided respectively between the first substrate 421 and the second substrate 422 and between the second substrate 422 and the third substrate 423. A ground electrode 48 is formed on the rear surface of the third substrate 423 while the ground electrode 48 is joined to the base structure 41.
The high frequency circuit elements 43 and the circuit pattern 45 are electrically connected to each other by means of the wirings W while the through halls 49 serve to electrically connect the circuit patterns 45 to 47 to each other and serve to electrically connect the ground electrode 48 and the circuit patterns 45 to 47 respectively.
In the case of the high frequency circuit apparatus in accordance with the conventional technique as illustrated in FIG. 1, when the circuit scale of the system is increased, the lengths of the wirings for supplying a bias voltage are increased resulting in an increased size of the apparatus. Furthermore, the use of an appropriate package, an appropriate shield plate or the like becomes inevitable so that it is difficult to put the high frequency circuit apparatus into commercial production and cut down the price.
In the case of the high frequency circuit apparatus in accordance with the conventional technique as illustrated in FIG. 2, the substrate on which the circuit patterns for transferring high frequency signals and direct current signals is multilayered. For this reason, the packing density can be increased and it is possible to form the apparatus in a smaller size. However, since the high frequency circuit elements are formed on an upper layer, heat has to be dissipated to the base structure through a plurality of the substrates which possess a little capability of radiating heat when it is need to dissipate heat as generated by the high frequency circuit elements such as power amplifier elements. Because of this, it is impossible to obtain an excellent thermal dissipation characteristics.
The present invention has been made in order to solve the shortcomings as described above. It is an object of the present invention to provide a high frequency circuit apparatus which is provided with excellent thermal dissipation characteristics and which is advantageous in shrinking the size and in improving the massproductivity.
In brief, the above and other objects and advantages of the present invention are provided by a new and improved high frequency circuit apparatus comprising:
a multilayer structure consisting of a plurality of insulating layers and a plurality of conductive layers, said insulating layers and said conductive layer being layered alternately with each other; and
a plurality of signal processing circuits provided on said multilayer structure and connected to each other by means of said conductive layer,
wherein said signal processing circuits include at least one high frequency circuit device driven at a high frequency and at least one low frequency circuit device driven at a low frequency lower than said high frequency; and
wherein at least part of said low frequency circuit is located on an upper layer of said multilayer structure while said high frequency circuit is located on a lower layer of said multilayer structure lower than said upper layer.
In a preferred embodiment, further improvement resides in that said multilayer structure is composed of a supporting base substrate and a multilayer substrate mounted on said supporting base substrate.
In a preferred embodiment, further improvement resides in that said high frequency circuit device is provided on said supporting base substrate.
In a preferred embodiment, further improvement resides in that said high frequency circuit device is provided on said supporting base substrate through a conductive film.
In a preferred embodiment, further improvement resides in that said conductive layers are composed of conductive patterns.
In accordance with a further aspect of the present invention, the above and other objects and advantages of the present invention are provided by a new and improved high frequency circuit apparatus comprising:
a multilayer structure consisting of a plurality of insulating layers and a plurality of conductive pattern layers, said insulating layers and said conductive pattern layer being layered alternately with each other; and
signal processing circuitry provided on said multilayer structure and connected to each other by means of said conductive pattern layer,
wherein said high frequency circuit apparatus is driven with high and low frequency signals; and
wherein said low frequency signal is transferred through an upper layer of said multilayer structure while said high frequency signal is transferred through a lower layer of said multilayer structure located lower than said upper layer.
In a preferred embodiment, further improvement resides in that said multilayer structure is composed of a supporting base substrate and a multilayer substrate mounted on said supporting base substrate.